If you have fuel leaking around the throttle shaft, running down the throat of the carb, or coming out the top of the carb, it’s flooding.

Follow these steps to determine the cause:

• Check the needle for damage to the viton tip. The tip is easily damaged when any pressure is put on it.
• Test the fuel pump - check your manual for the correct setting, but most single barrel carbs should be 3-4psi.
• Make sure there is a gasket under the needle and seat.
• Make sure the old gasket material was completely removed under the seat.
• Check float level.
• Test brass floats for leaks by submerging floats in hot water and checking for bubbles. Nitrophyl/plastic floats should be replaced at time of rebuild.
• Move the float up and down to verify it is not rubbing against the any surfaces or binding.
• Look for dirt particles in the bottom of the float bowl. Dirt may be getting into the needle and seat from a dirty fuel system. This will prevent the needle from sealing.
• Make sure the float isn’t rubbing on the float bowl gasket.
• Check the power valve in the bottom of the float bowl. The needle should be up, not bent. Also make sure the gasket under the valve isn’t damaged, or stacked.
• Is the fuel tank vented and is the vent clear? Some have an extra tube going to the tank and some vent through the gas cap.